The use of flexible packaging for storing and shipping food and other products is common. It is also known to provide opening mechanisms for controlled access to the contents of the package. The packaging materials may take many forms and may include multiple layers. It is also known to provide separate opening mechanisms for the individual layers within a package.
U.S. Pat. No. 1,641,408 to Bainbridge et al. shows a package having a secondary cover provided at one end and a sealing means to secure the cover to the end of the package. The cover portion wraps around the package and includes a perforation line within a folded extension of the cover. A metal clip is secured to the end of the package to retain the cover. Removal of the clip exposes the cover, which may be separated from the package by tearing along the perforation line.
U.S. Pat. No. 6,391,353 to Marbler et al. shows a multilayer package having a score line formed in the outer layer of the package and a separate score line formed on the inside layer of the package. Removal of a portion of the outside layer along the outside score line creates a hood or cap structure. The inside layer and the outside layer are attached at the end seal. Removal of the cap structure causes separation of an end portion of the inner layer along the inside score line.
U.S. Pat. No. 2,811,455 to Erekson shows a package having an inner container, including a separating score line, and an outer wrapper. A removal tape is provided under the outer wrapper, which overlaps the inner score line. An exposed end of the tape forms a starting tab to create a separation line through the outside layer. The separation of the outer wrapper exposes the inner score line for further separation of the top portion of the package.
US 2004/0022462 to Markham shows a multilayer package having opening mechanisms within various layers. The package includes a closed end in which both layers are secured together. A line of weakness may be formed in the outer layer, spaced from the closed end as well as within the inner layer. The line of weakness is spaced from an inner seal within the inner package. Additional lines of weakness are provided in the outer package layer and inner layer. Opening of the package is accomplished by tearing across the line of weakness, opening the outer package and exposing the inner package.